# JavaScript > JavaScript: 3 free modules that walk you through JavaScript: An Instant Quote Calculator for Your Website, JavaScript: Turn Invoice Dates into Due-Date… Source: https://learn.ynteractive.com/content/course/javascript · Updated 2026-10-24 · Free from Stepthrough (https://learn.ynteractive.com) Updated October 24, 2026 JavaScript: 3 free modules that walk you through JavaScript: An Instant Quote Calculator for Your Website, JavaScript: Turn Invoice Dates into Due-Date Reminders and JavaScript: Pull Contacts from an API into a Table, using JSFiddle. Each module is a real project. You watch a step, do it yourself in a practice copy of the tool, and it checks your work before moving on. It is free, and no experience is needed. ## 3 modules - [JavaScript: An Instant Quote Calculator for Your Website](https://learn.ynteractive.com/content/js-quote-calculator): A beginner JavaScript walkthrough in the free JSFiddle: a four-line HTML form and a few lines of JavaScript that turn square feet into a price, with a minimum charge… - [JavaScript: Turn Invoice Dates into Due-Date Reminders](https://learn.ynteractive.com/content/js-due-date-reminders): A beginner JavaScript walkthrough in the free JSFiddle: work out Net 30 due dates, count the days left and list every invoice as due or overdue, typing every line… - [JavaScript: Pull Contacts from an API into a Table](https://learn.ynteractive.com/content/js-api-contacts-table): A beginner JavaScript walkthrough in the free JSFiddle: fetch contact data from a free practice API and show name, company and email in a table, typing every line… ## What you do in each module - [JavaScript: An Instant Quote Calculator for Your Website](https://learn.ynteractive.com/content/js-quote-calculator) (about 12 minutes, 13 steps, beginner). You work through: The form, The price rule and Connect the button. - [JavaScript: Turn Invoice Dates into Due-Date Reminders](https://learn.ynteractive.com/content/js-due-date-reminders) (about 15 minutes, 11 steps, beginner). You work through: The list and today, Due dates and days left and Write the reminders. - [JavaScript: Pull Contacts from an API into a Table](https://learn.ynteractive.com/content/js-api-contacts-table) (about 12 minutes, 9 steps, beginner). You work through: Look at the data, Fetch it and Build the table. ## Common questions ### How long will this take? The 3 modules take about 39 minutes in total, and you can do them in separate sittings. ### Do I need experience first? No. These modules are beginner level, and each step tells you exactly where to click. ### Do I need a JSFiddle account to start? No. The practice runs in a copy of JSFiddle inside your browser, and nothing touches your real accounts. When you are ready, you repeat the steps in your own account. ### Is it free? Yes. All 3 modules are free. ### Where should I start? Start with [JavaScript: An Instant Quote Calculator for Your Website](https://learn.ynteractive.com/content/js-quote-calculator), then continue with [JavaScript: Turn Invoice Dates into Due-Date Reminders](https://learn.ynteractive.com/content/js-due-date-reminders). ## Related [AI Automation for Beginners (3)](https://learn.ynteractive.com/content/course/ai-automation-for-beginners) · [Business Automations (11)](https://learn.ynteractive.com/content/course/business-automations) · [Prompt Writing (8)](https://learn.ynteractive.com/content/course/prompt-writing) · [AI for Accounting & Bookkeeping Firms (12)](https://learn.ynteractive.com/content/industry/accounting-and-bookkeeping-firms) · [AI for Law Firms (6)](https://learn.ynteractive.com/content/industry/law-firms) · [AI for Insurance Agencies (5)](https://learn.ynteractive.com/content/industry/insurance-agencies) · [AI for Recruiting & HR (10)](https://learn.ynteractive.com/content/industry/recruiting-and-hr) · [AI for Consulting & Agencies (17)](https://learn.ynteractive.com/content/industry/consulting-and-agencies) · [AI for Real Estate (4)](https://learn.ynteractive.com/content/industry/real-estate) · [AI for Sales (13)](https://learn.ynteractive.com/content/industry/sales) · [AI for Marketing (19)](https://learn.ynteractive.com/content/industry/marketing) · [AI for Operations (24)](https://learn.ynteractive.com/content/industry/operations) · [AI for Finance (4)](https://learn.ynteractive.com/content/industry/finance) · [Accounting (3)](https://learn.ynteractive.com/content/course/accounting) · [AI Basics (22)](https://learn.ynteractive.com/content/course/ai-basics) · [AI Voice Agents (5)](https://learn.ynteractive.com/content/course/ai-voice-agents) · [Build Apps with Lovable (5)](https://learn.ynteractive.com/content/course/build-apps-with-lovable) · [ChatGPT for Everyday Work (17)](https://learn.ynteractive.com/content/course/chatgpt-for-everyday-work) · [Claude for Everyday Work (7)](https://learn.ynteractive.com/content/course/claude-for-everyday-work) · [Claude Skills (6)](https://learn.ynteractive.com/content/course/claude-skills) · [AI for Marketing (2)](https://learn.ynteractive.com/content/industry/marketing) · [Gemini for Google Workspace (6)](https://learn.ynteractive.com/content/course/gemini-for-google-workspace) · [Jump Start: Runable (2)](https://learn.ynteractive.com/content/course/jump-start-runable) · [Make.com Automation Basics (5)](https://learn.ynteractive.com/content/course/make-com-automation-basics) · [Microsoft 365 (3)](https://learn.ynteractive.com/content/course/microsoft-365) · [n8n Automation Toolkit (25)](https://learn.ynteractive.com/content/course/n8n-automation-toolkit) · [Project management (4)](https://learn.ynteractive.com/content/course/project-management) · [Python (3)](https://learn.ynteractive.com/content/course/python) · [RAG: chat with your own docs (2)](https://learn.ynteractive.com/content/course/rag-chat-with-your-own-docs) · [Runable for Entrepreneurs (3)](https://learn.ynteractive.com/content/course/runable-for-entrepreneurs) · [SQL (3)](https://learn.ynteractive.com/content/course/sql) · [Vibe Coding for Business (3)](https://learn.ynteractive.com/content/course/vibe-coding-for-business) · [Zapier Automation Basics (2)](https://learn.ynteractive.com/content/course/zapier-automation-basics) · [AI for Electrical (2)](https://learn.ynteractive.com/content/industry/electrical) · [AI for HVAC (2)](https://learn.ynteractive.com/content/industry/hvac) · [AI for Plumbing (2)](https://learn.ynteractive.com/content/industry/plumbing) · [JSFiddle tutorials (3)](https://learn.ynteractive.com/content/tool/jsfiddle) [All free tutorials](https://learn.ynteractive.com/content) ## How every module works Each step is shown on the left, with a cursor pointing to exactly where to click. You do the same thing on the right, in a practice copy of the real tool. Get it right and it moves on. Nothing touches your real accounts until you're ready to build it for real. [Start learning free](https://learn.ynteractive.com/)